Fire extinguisher



` Feb. 21, 1933.

FIRE

Filed March 14, 1952 H. w. DOUG'HTY EXTINGUI SHER 2 Sheets-Sheet l ATTORNEYS Feb. 21, 1933. H. wqDoUGHTY FIRE EXTINGUISHER Filed March 14 1952 2 Sheets-Sheet 2 INVENTOR Maud/ /fers ATTORNEY Patentedv Feb. 21,1933

PATENT oFFlcE l HOWARD' WATERS DOUGHTY, 0F AIIHEBBT, HASBACHUQETTS FIRE EXTINGUISHEE Application led March 14, 1932. Serial No. 598,73.

This invention relates to fire extinguishers and particularly to that type of extinishersfrom which a fire extinguishing iiid is'adapted to be discharged automaticall when the temperature in the vicinity of t e extinguisher rises to a predetermined point.

It is the object of the present invention to`provide a simple and effective extinguisher containing a fire extinguishing iuid and a fiuid which is maintained under pressure at normal atmospheric temperatures and is adapted to be released under suitable conditions, as for example when a fire occurs in the vicinity, so that the ire extinguishing fluid is discharged onto the burning area adjacent the extinguisher.

Another object of the invention is to avoid remature release of the fire extinguishing quid in the event of leakage of the iuid under pressure.

In carrying out the invention, I provide a rece tacle of any suitable material and form or the fire extinguishing fluid, such as carbon tetrachloride, and also rovide an outlet for the latter preferably with a sprinkler head of approved design. If the outlet is at the top of the receptacle, a tube should extend therefrom to the bottom of the receptacle to permit ejection of the contents. The outlet may, however, be placed at the bottom of the receptacle.

Within the receptacleand immersed in the fire extinguishing fluid, a suitable container for a Huid under pressure is disposed, so that it ma be withdrawn for refilling when reuire The container is closed by a remov-A a le cap having an outlet passage therein which communicates with the interior of the receptacle for the fire extinguishing fluid. The passage maybe sealed normally by a plug of fusible alloy such as Woodsmetal having a fusing point equal to the temperature at which the contents of the extinguisher are to be discharged. Such alloys are wellknown in the art and are commonly used in automatic sprinkler systems.

In the container, I may place a. suitable liquefied gas or solidified gas which will become liquid at the normal temperature of A velope the apparatus and under the pressure cle- Liquid orsolid carbon dioxide are su1table pressure developin agents. The former wlll remain a liqui at normal atmospherlc temperature under a pressure of 5 55 atmospheres, and the latter will be converted into llquid at such temperatures and at the'pressure of 5 atmospheres develo ed b the vaporization of a part of the car on d1- oxide. When the pressure is released, however, by the opening of the passage in the cap2 the liquid carbon dioxide will vaporize rapldly even at normal atmospheric temperatures and under hi her temperatures such as are developed in t e vicinity ofa fire, the' vaporlzation will be more rapid.

Consequently when the fusible plug melts as the result of heat transmitted through the cap, the gaseous pressure in the receptacle above the ire extinguishing fluid will increase rapidly and the fluid will be ejected through the outlet if the latter is open.

To avoid premature discharge, I preferably provide an outlet or sprinkler head withA a fusible plug of an alloy such as Woods metal or other suitable metal having a melting point such as to fuse when the temperature rlses to a predetermined point. Should any leak occur in the inner container in the absence of a temperature suiicient to melt 30 the latter plug, the fire extinguishing fluid will be retained, but if both plugs are melted by an increase in temperature due to a fire, the iuid will be. ejected immediately upon the surrounding surface.

The invention will be better understood by reference to the following description and the accompanying drawings, in which Fig. 1 is a vertical section through an apparatus embodying the invention;

Fig. 2 is a transverse section on the line 2-2 of Fig'l; and

Fig. 3 is a fragmentary view illustrating the application of the sprinkler head at the bottom of the receptacle.

Referring to the drawings, 5 indicates the receptacle for the fire extinguishing Huid. The receptacle, made preferably of a suitable metal, may be of any suitable form. It is filled preferably with a ire extinguishing 10 fluid such as carbon tetrachloride to approximately the level indicated by the hne X 1n the drawings.

To facilitate the removal or refilling of the container 6, the latter is made preferably in the form of an elongated tube of suitable metal and is threadedly secured at 7 to a cap 8 also of metal. 1t will be' noted that the cap 8 has a. downwardly extending flange 9 which is threaded to receive the upper end of the tubular container 6. The latter, being quite cold when it is connected to the cap, will be contracted somewhat, and upon the natural rise in temperature after the parts are assembled the tubular container Will expand. thus ensuring a gas-.tight joint at the threaded connection.

The cap 8 is provided with a passage 10 which is normally closed by a plug l1 of fusible metal adapted to become liquid at a predetermined tem pcrature at which the apparatus is designed to operate. rlChe passage 1G extends into the space within the receptacle 5 above the level of the tire extinguishing fluid therein. Thus when the plug l1 fuses the gaseous contents of the tubular container 6 are released to the space Within the receptacle 5 and atiord the necessary pressure to force the re extinguishing fluid therefrom.

rlhe cap 8 is threadedly secured at 12 to a ring 13 which may be Welded or otherwise 'fastened to the upper wall of the receptacle 5. rl`hus the cap and the tubular container 6 may be removed bodily trom the device when desired. Preferably the cap 8 is countersunk at le to facilitate transfer of heat to the fusible plug 11.

l'n the preferred form of the invention, a tube 15 extends through the top of the receptacle 5 to a point adjacent the bottom thereof and carries on its upper end a sprinkler head 16 having a passage 17 therein and a detiector 18 above the end of the passage to distribute the liquid over the surrounding surface. The passage 17 may be filled with a fusible metal 19 or otherfusible material adapted to melt at the temperature at which the device is designed to operate. Conveniently a frangible diaphragm may be disposed between a shoulder 20 and the threaded top 21 of the sprinkler head, thus introducing another element of resistance in the passage of the fire extinguishing fluid from the receptacle 5 through the sprinkler head.

In preparing the device. the receptacle 5 may be filled to the level indicated with a fire extinguishing fluid such as carbon tetrachloride. The tubular container 6 is detached from the cap 8 and is partially filled with a liqueied gas such as liquid carbon dioxide or with a solidified gas such as solid carbon dioxide. Other materials may be employed, but those described are best adapt-ed for use in the apparatus. Conveniently an insulating layer 22 of paper or other suitable material may be placed in the tubular container 6 to prevent premature vaporization while the parts are being assembled. The tubular container' is threadedly connected to the cap 8, the passa e 10 being previously sealed with the usile plug, and the cap is then introduced and threadedly secured in the ring 13 as indicated in the drawings. The apparatus may be disposed then in position for use should necessity arise. It will be understood that a portion of the liquefied gas will vaporize until an equilibrium is established. It a solidified gas is used, a ortion will likewise vaporize until an equili rium is established. Thereafter the liquid will remain in the tubular container 6 with a small amount of vapor under pressure until it is released by the fusing of the plug 11. W hen the plug 11 is fused, pressure will be released to the receptacle 5 and the contents of the receptacle will be ejected unless the passage in the sprinkler head is closed. Upon the occasion of a `fire, the passage 10 and the corresponding passage 17 in the sprinkler head Will be opened substantially simultaneously, and if a diaphragm is employed it will be ruptured by the pressure of the liquid under the action of the gas expanding 1n the interior of the receptacle 5.

ln F ig. 3 of the drawings, l have illustrated a modification of the device in which the same parts are employed except that the tube 15 is omitted and the sprinkler head 23 is secured to the bottom of the receptacle 5. The sprinkler head includes the same elements as in the previouly described embodiment of the invention. The only diderence is that the tire extinguishing duid is delivered from the bottom of the receptacle 5 rather than from the top. 'E he operation in' both cases is the same.

T he invention affords a simple and effective tire extinguishing structure with certainty ot1 operation and assurance against premature discharge by reason of inadvertent leakage of gas from the tubular container 6.

Various changes may be made in the form and arrangement of the device and the several parts thereof Without departing from the invention or sacrificing any of the advantages thereof.

l claim:

1. A. fire extinguisher comprising a closed receptacle for tire-extinguishing liquid, outlet means constructed and, )ositioned to normally prevent discharge o the liquid therethrough, said outlet means being open at predetermined fire temperature, a container within the receptacle adapted to hold a Huid under pressure and having a passage communicating with the interior of the receptacle, and means fusible at said predetermined fire temperature to normally close the passage, said fusible means being positioned to be aected by a rise of temperature adjacent the receptacle.

2. A fire extinguisher comprising a closed receptacle for fire-extinguishing liquid, out- 6 let means constructed and ositioned to normally prevent discharge o? the liquid there through, said outlet means being open at predetermined fire temperature, a container Within the receptacle adapted to hold a luid l@ under pressure, including a removable cap having a passage communicating withthe interior of the receptacle, and means fusible at said predetermined fire temperature to normally close the passage, said fusible 145 means being positioned to be affected by a rise of temperature adjacent the receptacle.

El A. ire extinguisher comprising a closed receptacle for fire-extinguishing liquid, outlet means constructed and fpositioned to normally prevent discharge o the liquid therethrong said outlet means being openat predetermined ire temperature, a container within the receptacle adapted to hold a fluid under pressure, including a removable cap threadedly secured to the receptacle and to the container and having a passage communicating with the interior of the receptacle, and means fusible at predetermined temperature to normally close the passage, said fusible means being positioned to be affected by arise of temperature adjacent the rece tacle.

4. A re extinguisher comprising a closed receptacle for fire-extinguishing liquid, outlet means including a distributor head constructed and positioned to normally prevent discharge of the liquid therethrough, said outlet means being open at predetermined fire temperature, a container within the re- 40 ceptacle adapted to hold-a fluid under pressure and having a Passage communicating with the interior o the receptacle, means fusible at predetermined tem erature to normally close the passage, sai fusible means being positioned to be affected by a rise of temperature adjacent the receptacle.

5. A lire extinguisher comprising a receptacle for fire extinguishing liquid, an outlet therefrom including a distributor head with a passage therein and means fusible at predetermined temperature normall closing the passage, a container within t e receptacle adapted to hold a iluid under pressure and having a passage communicating with the interior of the rece tacle and means fusible at predetermined re temperature to normally close the passage, said fusible means being positioned to be alfected by a rise of temperature adjacent the receptacle.

6. .A fire extinguisher comprisin a receptacle for fire extinguishing liqui an outlet therefrom including a distributor head with a passage therein and means fusible at predetermined temperature normall clos- 05 ing the passage, a container within t e receptacle adapted to hold a fluid under pressure includin a removable cap having a passage communicating with the interior of the receptacle and means fusible at predetermined re ltemperature to normally close the passage, said fusible means being positioned to be affected by a rise of temperature adjacent the receptacle.

7. A fire extinguisher comprising a receptacle for fire extinguishing liquid, an outlet therefrom including a distributor head with a passage therein and means fusible at predetermined temperature normally closing the passage, a container within the receptacle adapted to hold a fluid under pressure, including a removable cap threadedly secured to the receptacle and to the container and having a passage communicating with the interior of the receptacle, and means fusible at predetermined fire tem rature to normally close the passage, said fusible means being positioned to be alfected by a rise of temperature adjacent the receptacle.

In testimony whereof I ailix my signature.

HOWARD WATERS DOUGHTY. 

